Tissue Flashcards
exam 1
what 3 things is classification of tissue based on?
- structure of cells
- composition of extracellular matrix
- cell function
epithelial tissue (structure, EC matrix, function)
one or more layers of closely packed cells, little to no EC matrix. Covers body surfaces, lines body/organ cavities, forms glands.
6 characteristics of epithelial tissue
- cellularity (tightly packed)
- distinct cell surfaces
- attached to basement membrane
- avascular
- innervation (high nerve supply)
- high regeneration capacity
3 distinct surfaces of epithelial tissue
- free (apical)
- lateral
- basal
free (apical) surface
in epithelial tissue, not attached to other cells, exposed either to the external environment or some internal body space
basement membrane
specialized type of EC material secreted by epithelial and connective tissues, strengthens attachment and forms a barrier between epithelium and underlying connective tissue
lateral surface
in epithelial tissue, attached to other epithelial cells
basal surface
in epithelial tissue, attached to the basement membrane
basement membrane layers
basal lamina
reticular lamina
how is epithelial tissue classified?
number of cell layers
shape of cells at apical surface
Functions of epithelial tissue
(no one structure in the body does all)
1. protect underlying structures (from dehydration, abrasion, destruction)
- selective permeability
- secreting substances
- sensation
simple epithelium
single layer of cells extending from basement membrane to free surface, typically in areas with minimum stress
stratified epithelium
more than one layer, but only the deepest layer attaches to the basement membrane, found in areas subject to stress
pseudostratified epithelium
type of simple epithelium that appears stratified due to nuclei in different locations
squamous epithelial tissue
cells are flat or scale like
transitional epithelial tissue
cells change shape as the organs stretch to a larger size and then collapse back to original shape, cuboidal to squamous
columnar epithelial tissue
cells are taller than they are wide
cuboidal epithelial tissue
cells are cube shaped
Where is simple epithelial tissue found
areas where filtration, absorption, secretion are the primary function
where is stratified epithelial tissue found
areas likely to be subject to abrasive activity or mechanical stress (skin)
what is squamous epithelial tissue used for
diffusion/filtration
cell junctions
areas where adjacent cells are attached
what is cuboidal/columnar epithelial tissue used for
absorption and secretion
tight junctions
strands of proteins at the apical surface around the circumference of each adjacent cell, prevents substances from passing into the cell
desmosomes
provide structural integrity to cells that have exposure to stress- also anchors the basal surface to underlying basement membrane
gap junction
provides a passageway for substances to move in between neighboring cells
glands
organs composed of epithelial tissue which secrete substances
connective tissue types
connective tissue proper, supporting, fluid
connective tissue description
contains a variety of cell types within an abundant extracellular matrix and often has protein fibers, found in every organ
cells of connective tissue
- leukocytes (white blood cells)
- macrophages (internalize foreign material)
- fibroblasts (synthesize collagen)
- adipocytes
- platelets
- mast cells
- stem cells
components of connective tissue extracellular matrix
- protein fibers
- ground substance
- fluid
types of protein fibers found in connective tissue
- collagen fiber (strong, flexible, inelastic)
- reticular fiber (branch between tissue and organs)
- elastic fibers
ground substance
lacks shape and fills space between cells and protein fibers in connective tissue
loose connective tissue
acts as “packing material”, contains loosely arranged collagenous fibers, well vascularized
dense connective tissue
protein fibers forming thick bundles filling nearly all extracellular space
areolar connective tissue
what type of ct, makeup, location
type of loose CT, mainly collagen and some elastic fibers, abundant ground substance, found almost everywhere, from skin to blood vessels
adipose connective tissue
what type of ct, makeup, location
type of loose CT which is highly vascular, mainly adipocytes with small ECM, found around kidneys and heart, protects and insulates, stores energy
Reticular Connective tissue
type of loose CT which forms the framework of lymphatic tissue
Dense regular connective tissue
protein fibers oriented in 1 direction
1. dense regular collagenous: has abundant collagen fiber, tendons and ligaments
- dense regular elastic: allows for stretch and recoil, vocal chords
dense irregular connective tissue
protein fibers arranged randomly
1. dense irregular collagenous: forms most of dermis, covers some bone and cartilage
- dense irregular elastic: found in elastic arteries
supporting connective tissue types
- cartilage- avascular, no nerves, extensive ECM
- bone- hard connective tissue composed of living cells
types of cartilage
- hyaline: a lot of protein fiber, smooth surface (costal in ribs)
- fibrocartilage: very tough (mandible joint)
- elastic: rigid but maintains properties (nose tip)
types of bone
spongey bone, compact bone
types of fluid connective tissue
blood (plasma and formed elements)
lymph
